Plant-Based Investigation of Microplastics in Constructed Wetland Systems

Abstract

Microplastics, defined as plastic particles smaller than 5 mm in size, have been detected in many receiving environments, particularly aquatic ecosystems. Constructed wetland systems are a system that prevents these particles from reaching receiving environments at high rates in rural areas. The role of constructed wetland plants in microplastic removal, an important component of this system, is not fully understood. Within the scope of this study, the microplastic removal potential of Phragmites australis plants was investigated in a subsurface flow constructed wetland system located in Denizli province. Plant samples, including roots, stems, and shoot tips, collected from both the influent and treated water zones were thoroughly examined for the presence of microplastics. After performing extraction on the plant samples, a higher concentration of microplastics was detected in the influent zone compared to the treated water zone. The highest microplastic concentration was detected in the stems of plants from the influent zone (653.33 MP/g). Similarly, in the treated water zone, stems also exhibited the highest microplastic concentration (623.33 MP/g). The color spectrum of microplastics showed a comparable distribution between the influent and treated water zones, with white-transparent particles being the most abundant. In the influent zone, the proportion of white-transparent microplastics was 84.69% in the body, 69.85% in the root, and 75.76% in the shoot tip. In the treated water zone, the respective proportions were 75.94% in the stem, 70.63% in the root, and 79.19% in the shoot tip. Based on their morphology, microplastics were classified as fibers and films, with fibers being the dominant type across all samples. In the influent zone, the fiber distribution was 79.41% in the root, 66.33% in the stem, and 74.55% in the shoot tip. In the treated water zone, the distribution was 83.33% in the root, 64.17% in the stem, and 67.79% in the shoot tip. Furthermore, chemical analyses of plant parts revealed the presence of polyethylene terephthalate (PET) and polyethylene (PE) polymers in the influent zone, whereas PET, PE, and polypropylene (PP) polymers were identified in the treated water zone.

Keywords

• Constructed Wetland
• Microplastic
• Phragmites Australis

Project Number

2021FEBE005

Yapay Sulakalan Sistemlerinde Bitki Temelli Mikroplastik İncelemesi

Abstract

Mikroplastikler olarak tanımlanan ve boyutu 5 mm’den küçük olan plastik parçacıklar, sucul ekosistem başta olmak üzere birçok alıcı ortamda tespit edilmektedir. Yapay sulakalan sistemleri, kırsal bölgelerde bu parçacıkların alıcı ortamlara ulaşmasını yüksek oranlarda önleyen bir sistemdir. Bu sistemin önemli bir parçası olan yapay sulakalan bitkilerinin mikroplastik giderimindeki rolü tam anlamıyla bilinememektedir. Bu çalışma kapsamında, Denizli ilinde bulunan bir yüzey altı akışlı yapay sulakalan sisteminde Phragmites australis bitkisinin mikroplastik giderim potansiyeli araştırılmıştır. Giriş ve arıtılmış su bölgesinden toplanan bitki örneklerinin kök, gövde ve sürgün ucu bölgeleri mikroplastik varlığı açısından kapsamlı şekilde incelenmiştir. Bitki numunelerinde gerçekleştirilen ekstraksiyon işlemleri sonrasında giriş bölgesinde, arıtılmış su bölgesine kıyasla daha yüksek miktarda mikroplastik tespit edildiği ortaya çıkmıştır. Giriş bölümünde en fazla mikroplastik yoğunluğuna gövde bölümünde rastlanmıştır (653,33±13,27 MP/g). Arıtılmış su bölgesinde de gövde bölümü en yoğun mikroplastik içeriğine sahip bölüm olarak tespit edilmiştir (623,33±13,86 MP/g). Mikroplastiklerin renk skalası giriş ve çıkış bölgelerinde benzer dağılım göstererek en fazla beyaz-şeffaf renkli mikroplastiklere rastlanmıştır. Girişte beyaz-şeffaf renk dağılımı; gövde (%84,69), kök (%69,85), sürgün ucu (%75,76) iken arıtılmış suda; gövde (%75,94), kök (%70,63), sürgün ucu (%%79,19) şeklindedir. Mikroplastikler şekillerine göre lif ve film olarak tanımlanmıştır. Lif, tüm numunelerde en sık karşılaşılan şekil olmuştur. Girişte lif dağılımı; kök (%79,41), gövde (%66,33), sürgün ucu (%74,55) olarak belirlenmiştir. Arıtılmış suda ise; kök (%83,33), gövde (%64,17), sürgün ucu (%67,79) şeklinde bir dağılım ortaya çıktığı görülmüştür. Ayrıca bitki bünyesinde yürütülen kimyasal analizler sonucunda, giriş bölgesinde polietilen tereftalat (PET) ve polietilen (PE) polimeri; arıtılmış su bölgesinde ise PET, PE ve polipropilen (PP) polimerlerine rastlanmıştır.

Keywords

• Mikroplastik
• Phragmites Australis
• Yapay Sulakalan

Supporting Institution

Pamukkale Üniversitesi

Project Number

2021FEBE005

Ethical Statement

Hazırlanan makalede etik kurul izni alınmasına gerek yoktur. Hazırlanan makalede herhangi bir kişi/kurum ile çıkar çatışması bulunmamaktadır.

Thanks

Bu çalışma Pamukkale Üniversitesi Bilimsel Araştırma Projesi tarafından 2021FEBE005 nolu proje ile desteklenmiştir.

References

1. Andrady AL, Neal MA. Applications and societal benefits of plastics. Philosophical Transactions of the Royal Society B: Biological Sciences 2009;364(1526):1977-1984. doi:10.1098/rstb.2008.0304
2. Meikle JL. American plastic: a cultural history. 2000. Erişim adresi: [https://books.google.com/books/about/American_Plastic.html?hl=tr&id=u_1ePU4GEGAC]
3. Gilbert M. Plastics Materials: Introduction and Historical Development. In: Brydson's Plastics Materials: Eighth Edition; 2017, p. 1-18. doi:10.1016/B978-0-323-35824-8.00001-3
4. Geyer R, Jambeck JR, Law KL. Production, use, and fate of all plastics ever made. Science Advances 2017;3(7). doi:10.1126/sciadv.1700782/SUPPL_FILE/1700782_SM.PDF
5. Houssini K, Li J, Tan Q. Complexities of the global plastics supply chain revealed in a trade-linked material flow analysis. Communications Earth & Environment 2025;6(1):1-11. doi:10.1038/s43247-025-02169-5
6. Thompson RC, Moore CJ, Saal FSV, Swan SH. Plastics, the environment and human health: current consensus and future trends. royalsocietypublishing.org 2009;364(1526):2153-2166. doi:10.1098/rstb.2009.0053
7. Wright SL, Thompson RC, Galloway TS. The physical impacts of microplastics on marine organisms: A review. Environmental Pollution 2013;178:483-492. doi:10.1016/j.envpol.2013.02.031
8. Browne MA, Crump P, Niven SJ, Teuten E, Tonkin A, Galloway T, et al. Accumulation of microplastic on shorelines woldwide: Sources and sinks. Environmental Science and Technology 2011;45(21):9175-9179. doi:10.1021/es201811s

9. Kadlec RH, Wallace S. Treatment Wetlands. In: Treatment Wetlands; 2008. doi:10.1201/9781420012514
10. del Refugio Cabañas-Mendoza M, Olguín EJ, Sánchez-Galván G, Melo FJ, Barrientos MSA. Contribution of the root system of Cyperus papyrus and Pontederia sagittata to microplastic removal in floating treatment Wetlands in two urban ponds. Ecological Engineering 2024;206:107334. doi:10.1016/j.ecoleng.2024.107334
11. Yuan W, Xu EG, Li L, Zhou A, Peijnenburg WJGM, Grossart HP, et al. Tracing and trapping micro- and nanoplastics: Untapped mitigation potential of aquatic plants? Water Research 2023;242:120249. doi:10.1016/j.watres.2023.120249
12. Yin J, Zhu T, Li X, Wang F, Xu G. Phytoremediation of microplastics by water hyacinth. Environmental Science and Ecotechnology 2025;24:100540. doi:10.1016/j.ese.2025.100540
13. Göçmez S, Güngör M, Akyürek A, Şenyurt M, Öztürk A, Karabuğa MÇ. Revision of the constructed wetlands in Denizli city: the case study of Bozkurt-Alikurt constructed wetland. In: International Symposium on Urban Water and Wastewater Management; 2018.
14. Baylan N. Yapay sulakalanlarda mikroplastik gideriminin belirlenmesi [Yüksek Lisans Tezi]. Denizli: Pamukkale Üniversitesi Fen Bilimleri Enstitüsü; 2022.
15. APHA. Standard Methods for the Examination of Water and Wastewater 22nd Edition. Am. Public Heal. Assoc. Am. Water Work. Assoc. Water Environ. Fed.; 2012.
16. Baylan N, Koyuncuoğlu P, Erden G. Microplastics in a horizontal subsurface flow constructed wetland: A Case Study of Denizli/Türkiye. Ecological Engineering 2024;207:107349. doi:10.1016/j.ecoleng.2024.107349
17. Azeem I, Adeel M, Ahmad MA, Shakoor N, Jiangcuo GD, Azeem K, et al. Uptake and accumulation of nano/microplastics in plants: a critical review. Nanomaterials 2021;11(11):2935.
18. Prathna TC. Significance of microbial volatiles in ecological health: Impact on wetland systems. In: Volatiles and metabolites of microbes. Academic Press; 2021, p. 163-176.
19. Pamukoğlu MY. Akuaponik (Biyolojik Arıtma Tekniği) Tekniği ile Balık Atıksularının Arıtılması. İklim Değişikliği ve Çevre 2018;3(2):1-9.
20. Li Y, Zhang J, Xu L, Li R, Zhang R, Li M, et al. Leaf absorption contributes to accumulation of microplastics in plants. Nature 2025:1-8.
21. Ali I, Ding T, Peng C, Naz I, Sun H, Li J, et al. Micro- and nanoplastics in wastewater treatment plants: Occurrence, removal, fate, impacts and remediation technologies - A critical review. Chemical Engineering Journal 2021;423:130205. doi:10.1016/j.cej.2021.130205
22. Zahra SI, Iqbal MJ, Ashraf S, Aslam A, Ibrahim M, Yamin M, et al. Comparison of Ambient Air Quality among Industrial and Residential Areas of a Typical South Asian City. Atmosphere 2022;13(8):1168. doi:10.3390/atmos13081168
23. Gao M, Li C, Li Y, Wen S, Zhang Y, Liu L, et al. Integration of ecological restoration and landscape aesthetics: Mechanisms of microplastic retention by optimization of aquatic plants landscape design in urban constructed wetlands - A case study of the living water park in Chengdu. Science of The Total Environment 2024;957:177331. doi:10.1016/j.scitotenv.2024.177331
24. Wang H, Liang QB, Dai LY, Wang YX, Li XL, Hou L. [Effect of Free Water Surface Constructed Wetland on the Occurrence Characteristics of Microplastics in Water in the Upper Reaches of the Erhai Lake]. Huan jing ke xue= Huanjing kexue 2024;45(11):6616-6624. doi:10.13227/j.hjkx.202312273
25. Bretas Alvim C, Mendoza-Roca JA, Bes-Piá A. Wastewater treatment plant as microplastics release source - Quantification and identification techniques. Journal of Environmental Management 2020;255:109739. doi:10.1016/j.jenvman.2019.109739
26. Diez-Pérez DB, Arenas I, Maidana E, López-Rosales A, Andrade JM, Muniategui-Lorenzo S. Microplastics in surface water of the Bay of Asunción, Paraguay. Marine Pollution Bulletin 2023;192:115075. doi:10.1016/j.marpolbul.2023.115075
27. Navarro CKP, Arcadio CGLA, Similatan KM, Inocente SAT, Banda MHT, Capangpangan RY, et al. Unraveling Microplastic Pollution in Mangrove Sediments of Butuan Bay, Philippines. Sustainability 2022;14(21):14469. doi:10.3390/su142114469
28. Sajorne RE, Cayabo GDB, Madarcos JRV, Madarcos KG, Omar DM, Ardines LB, et al. Occurrence of COVID-19 personal protective equipment (PPE) litters along the eastern coast of Palawan Island, Philippines. Marine Pollution Bulletin 2022;182:113934. doi:10.1016/j.marpolbul.2022.113934
29. Napper IE, Baroth A, Barrett AC, Bhola S, Chowdhury GW, Davies BFR, et al. The abundance and characteristics of microplastics in surface water in the transboundary Ganges River. Environmental Pollution 2021;274:116348. doi:10.1016/j.envpol.2020.116348
30. Lares M, Ncibi MC, Sillanpää M, Sillanpää M. Occurrence, identification and removal of microplastic particles and fibers in conventional activated sludge process and advanced MBR technology. Water Research 2018;133:236-246. doi:10.1016/j.watres.2018.01.049
31. Van Do M, Le TXT, Vu ND, Dang TT. Distribution and occurrence of microplastics in wastewater treatment plants. Environmental Technology & Innovation 2022;26:102286. doi:10.1016/j.eti.2022.102286
32. Warren RJ, Cooper RJ, Mayes AG, Nolte S, Hiscock KM, Tosney J. Sewage derived microplastic and anthropogenic fibre retention by integrated constructed wetlands. Water, Air, & Soil Pollution 2024;235(6):361.
33. Browne MA, Crump P, Niven SJ, Teuten E, Tonkin A, Galloway T, et al. Accumulation of microplastic on shorelines woldwide: sources and sinks. Environmental Science & Technology 2011;45(21):9175-9179.
34. Sotiropoulou M, Stefanatou A, Schiza S, Petousi I, Stasinakis AS, Fountoulakis MS. Removal of microfiber in vertical flow constructed wetlands treating greywater. Science of the Total Environment 2023;858:159723.
35. Talvitie J, Mikola A, Koistinen A, Setälä O. Solutions to microplastic pollution-Removal of microplastics from wastewater effluent with advanced wastewater treatment technologies. Water Research 2017;123:401-407.
36. Huang S, Jiang R, Craig NJ, Deng H, He W, Li JY, et al. Accumulation and re-distribution of microplastics via aquatic plants and macroalgae-A review of field studies. Marine Environmental Research 2023;187:105951.